Thanking you kindly, sir, that's a relief!
Seems to work at all ranks, too.
I don't think it's in the Voc (under { ), or my eyesight is getting really
bad. Should be, IMHO, fairly crucial thing for an array-programming
language.
On 29 May 2014 11:23, Kip Murray <[email protected]> wrote:
> i. 4 4
> 0 1 2 3
> 4 5 6 7
> 8 9 10 11
> 12 13 14 15
> (<2 1) { i. 4 4
> 9
>
>
> On Thursday, May 29, 2014, alexgian <[email protected]> wrote:
>
> > If I want to index into a (rank 2) array to get the element usually
> called
> > the (i,j)th in the big, bad world, is there a better way to do it than
> > this, which I currently use?
> >
> > idx =: (1 { [) { ] {~ 0 { [
> >
> > 2 1 idx 4 4 $i.16
> >
> > 9
> >
> > I notice that if { takes an array as left arg, it merely returns the
> given
> > rows of that array, rather than the required indexed element.
> > So I can't do, for instance, (2 1) { 4 4 $i.16 and get what I want
> > Furher, I wander if there is a more generic way of writing this so that
> it
> > would work automatically for rank-3 arrays and greater.
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> >
>
>
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